Bug 1536062: Make sure that dead-code doesn't prevent ion compilation of wasm modules; r=lth

This also fixes-up a few places in text-to-binary where no error messages were
generated, resulting in incorrect out-of-memory messages.

Differential Revision: https://phabricator.services.mozilla.com/D23838

--HG--
extra : moz-landing-system : lando

js/src/jit-test/tests/wasm/gc/anyref.js

@@ -463,3 +463,22 @@ let glutenFreeBaguette = new Baguette("calories-free bread");
 exports.set_mut(glutenFreeBaguette);
 assertEq(exports.get_mut(), glutenFreeBaguette);
 assertEq(exports.get_mut().calories, "calories-free bread");
+
+// Make sure that dead code doesn't prevent compilation.
+wasmEvalText(
+    `(module
+       (func
+         (return)
+         (ref.null)
+         (drop)
+        )
+    )`);
+
+wasmEvalText(
+    `(module
+       (func (param anyref)
+         (return)
+         (ref.is_null (get_local 0))
+         (drop)
+        )
+    )`);

js/src/jit-test/tests/wasm/gc/tables-multiple.js

@@ -434,3 +434,51 @@ assertErrorMessage(() => wasmEvalText(
                    SyntaxError,
                    /parsing wasm text/);
 
+// Make sure that dead code doesn't prevent compilation.
+wasmEvalText(
+    `(module
+       (table (export "t") 10 anyref)
+       (func (param i32)
+         (return)
+         (table.get (get_local 0))
+         (drop)
+        )
+    )`);
+
+wasmEvalText(
+    `(module
+       (table (export "t") 10 anyref)
+       (func (param i32) (param anyref)
+         (return)
+         (table.grow (get_local 1))
+         (drop)
+        )
+    )`);
+
+wasmEvalText(
+    `(module
+       (table (export "t") 10 anyref)
+       (func (param i32) (param anyref)
+         (return)
+         (table.set (get_local 0) (get_local 1))
+        )
+    )`);
+
+wasmEvalText(
+    `(module
+       (table (export "t") 10 anyref)
+       (func
+         (return)
+         (table.size)
+         (drop)
+        )
+    )`);
+
+wasmEvalText(
+    `(module
+       (table (export "t") 10 anyref)
+       (func
+         (return)
+         (table.copy (i32.const 0) (i32.const 1))
+        )
+    )`);

js/src/jit-test/tests/wasm/passive-segs-nonboundary.js

@@ -1229,3 +1229,33 @@ function checkRange(arr, minIx, maxIxPlusOne, expectedValue)
     checkRange(b, 64827, 64834, 26);
     checkRange(b, 64834, 65536, 0);
 }
+
+// Make sure dead code doesn't prevent compilation.
+wasmEvalText(
+    `(module
+       (memory 0 10)
+       (data (i32.const 0))
+       (func
+         (return)
+         (memory.init 0)
+        )
+    )`);
+
+wasmEvalText(
+    `(module
+       (memory 0 10)
+       (func
+         (return)
+         (memory.fill)
+        )
+    )`);
+
+wasmEvalText(
+    `(module
+       (table (export "t") 10 funcref)
+       (elem (i32.const 0) 0)
+       (func
+         (return)
+         (elem.drop 0)
+        )
+    )`);

js/src/wasm/WasmIonCompile.cpp

@@ -2922,7 +2922,7 @@ static bool EmitMemOrTableCopy(FunctionCompiler& f, bool isMem) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -2982,7 +2982,7 @@ static bool EmitDataOrElemDrop(FunctionCompiler& f, bool isData) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -3023,7 +3023,7 @@ static bool EmitMemFill(FunctionCompiler& f) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -3068,7 +3068,7 @@ static bool EmitMemOrTableInit(FunctionCompiler& f, bool isMem) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -3133,7 +3133,7 @@ static bool EmitTableGet(FunctionCompiler& f) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -3189,7 +3189,7 @@ static bool EmitTableGrow(FunctionCompiler& f) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -3239,7 +3239,7 @@ static bool EmitTableSet(FunctionCompiler& f) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -3287,7 +3287,7 @@ static bool EmitTableSize(FunctionCompiler& f) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   uint32_t lineOrBytecode = f.readCallSiteLineOrBytecode();
@@ -3328,7 +3328,7 @@ static bool EmitRefNull(FunctionCompiler& f) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   MDefinition* nullVal = f.nullRefConstant();
@@ -3346,7 +3346,7 @@ static bool EmitRefIsNull(FunctionCompiler& f) {
   }
 
   if (f.inDeadCode()) {
-    return false;
+    return true;
   }
 
   MDefinition* nullVal = f.nullRefConstant();

js/src/wasm/WasmTextToBinary.cpp

@@ -3701,6 +3701,9 @@ static AstDataOrElemDrop* ParseDataOrElemDrop(WasmParseContext& c,
                                               bool isData) {
   WasmToken segIndexTok;
   if (!c.ts.getIf(WasmToken::Index, &segIndexTok)) {
+    UniqueChars msg = JS_smprintf("expected %s segment reference",
+                                  isData ? "data" : "element");
+    c.ts.generateError(c.ts.peek(), msg.get(), c.error);
     return nullptr;
   }
 
@@ -3742,6 +3745,8 @@ static AstMemOrTableInit* ParseMemOrTableInit(WasmParseContext& c,
   WasmToken segIndexTok;
   if (isMem) {
     if (!c.ts.getIf(WasmToken::Index, &segIndexTok)) {
+      c.ts.generateError(c.ts.peek(), "expected data segment reference",
+                         c.error);
       return nullptr;
     }
     segIndex = segIndexTok.index();